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NEETPhysicsLaws of Motion

Assertion : Friction opposes motion of a body. Reason : Static friction is self adjusting while kinetic friction is constant.

Options

  1. AIf both Assertion and Reason are correct and Reason is the correct explanation of Assertion
  2. BIf both Assertion and Reason are true but Reason is not the correct explanation of Assertion
  3. CIf Assertion is true but Reason is false
  4. DIf Assertion is false but Reason is true

Correct answer

D. If Assertion is false but Reason is true

Step-by-step solution

Check assertion - Friction opposes relative motion or the tendency of relative motion at the contact, not "motion of a body" in every situation; for example, while walking, friction aids forward motion, so the blanket statement is false. Check reason - Static friction adjusts up to its limiting value to match the applied force, whereas kinetic friction is approximately constant during sliding, making the reason correct.

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